At the Stennis Space Center, National Aeronautics and Space Administration’s (NASA) largest rocket engine test facility in Mississippi, Rammed Aggregate Pier® elements from Geopier were selected as a ground improvement method to support the new 20,000 sq ft staging area on 12-in. thick reinforced tarmac. The heavy loads associated with the rocket support pedestals resulted in an approximate 3,000 psf contact stress acting upon the pavement slab and underlying soils.The soil conditions consisted of 10 to 25 ft of loose sands and silty sands, which are common in the Gulf Coast.
To support the rocket pedestal loads while minimizing post-construction settlements, Geopier geotechnical engineers designed a ground improvement solution that consisted of displacement X1® piers. These vertically-compacted, displacement piers were constructed with sand, and not only provided an array of stiff pier elements but also densified the native loose sands during the construction process. A total of 400 Geopier displacement X1 piers were installed in the new tarmac area in 22 days.